This integrated research and training plan will prepare Dr. Ranney, a fellowship-trained, practicing emergency physician, to become an independently funded physician-researcher with expertise in emergency department (ED)-based mental health interventions. Dr. Ranney's long-term research goal is to become an expert in developing effective, easily-disseminated, technology-augmented mental health interventions for high-risk ED patients. Her short-term goals, for this K23 Mentored Patient Oriented Career Development Award, are to (1) gain expertise in the development and evaluation of technology-augmented ED depression interventions, and (2) to test the hypothesis that a brief in-ED + longitudinal text-message (ED+text) indicated depression prevention intervention is acceptable and feasible for high-risk youth. Depressive symptoms and peer violence are common, significant, and strongly correlated causes of morbidity, mortality, and ED visits among adolescents. The ED is often the primary source of care for high-risk youth with depressive symptoms and history of peer violence. The ED is well established as a location for mental health intervention, yet few resources are available to high-risk youth. Most adolescent ED patients use text-messaging. Text-message behavioral change has been shown effective. In this project, Dr. Ranney and mentors will develop and pilot a single-session in-ED + 8 week longitudinal text-message program (ED+text) to reduce depressive symptoms, for adolescent ED patients with depressive symptoms and a history of peer violence. Under the guidance of a strong mentorship team of NIH-funded researchers, Dr. Ranney will achieve five specific training goals: (1) Gain advanced training in ED-based mental health research, focusing on the link between depression and violence; (2) Develop expertise in use of technology, particularly text-messaging, to enhance intervention delivery and evaluation; (3) Become a skilled user of qualitative research methodology to inform intervention development; (4) Learn how to design and conduct a clinical trial of an ED-based depression prevention intervention; (5) Develop skills in longitudinal data analysis for clinical trials. Dr. Ranney's training activities will be complemented by an innovative research plan allowing practical application of her new skills. Using a staged approach, Dr. Ranney will, first, conduct focus groups to develop our innovative ED+text intervention content; next, refine the intervention through an iterative process of open trials; finally, test the acceptability and feasibility of the intervention through a randomized piot study (n=100). This work is a crucial step toward preventing depression and co-occurring disorders among a high-risk population that does not typically seek out services. It addresses a current lack of easily-accessible preventive interventions, addressing NIMH Strategic Objectives 3 (treatment development for diverse populations) and 4 (strengthening public health impact), as well as critical Adolescent and Mental Health objectives of Healthy People 2020.